The Astros have been one of baseball's most active teams at the Trade Deadline the past two years under former general manager Ed Wade, trading away Roy Oswalt and Lance Berkman in 2010 and Jeff Keppinger, Hunter Pence and Michael Bourn in '11.

The blueprint Houston is using to try to rebuild as it prepares to move to the American League next year is stockpile young talent while casting off pricey veterans like Lee, who was in the last year of his six-year, $100 million deal.

In the trades they have made in July the last two years, including Lee, the Astros have acquired 17 players in return, including Major Leaguers J.A. Happ (Phillies for Oswalt) and Jordan Schafer (Braves for Bourn). Some of the players they've received, such as Jonathan Singleton and Jarred Cosart, are among the team's top prospects.

"We want to build as competitive as a team as we can, and we also want to build the organization for sustained success in the future," said Luhnow, who took over in December. "That's a balance that sometimes is in conflict with one another, and those are the decisions that become tough when you have players who are contributing and could potentially get you something for the future."

Rodriguez, a veteran lefty who's 7-6 with a 3.38 ERA and is the team's last holdover from the 2005 World Series, could have the most trade value, but there will be significant money issues. Rodriguez is making $10 million this year, $13 million in 2013 and has a $13 million option for '14 that's vested if he gets traded.

Myers, who started 66 games his first two years in Houston before moving to closer this year, is making $11 million this year and has a $13 million option for '13 that is vested if he finished 45 games. The vesting option was reworked after Myers agreed to move to closer in March.

Lyon has put together a solid season in middle relief after missing most of last year following arm surgery. He's in the final year of a three-year, $15 million contract, so teams taking on his contract won't have a long-term financial commitment.

The Astros paid most of the remaining $9 million on Lee's salary when they dealt him to the Marlins, and they will likely have to eat some more money in dealing any of their remaining big-money players.

"There's a lot of dialogue this time of year among all clubs," Luhnow said. "There's three camps. There's teams that clearly have needs and they're needing to fill those needs because they feel like they can close in on the playoff hunt or want to bolster their chances. There's teams in the middle trying to decide which way they want to go. And there's teams that this time of year aren't contenders and have assessed what other teams might want."

The Astros are clearly in the latter group and will try to pluck more top prospects away from clubs craving some of their veteran talent.